1. Field of the Invention
The invention relates to an electrical connector, and more particularly to a socket structure with duplex electrical connection.
2. Related Art
The most popular signal transmission specification of the modern computer apparatus is the universal serial bus (USB). A connector socket and a transmission cable satisfying this specification may make peripheral apparatuses, such as a mouse, a keyboard and the like, which are externally connected to the computer, be immediately detected and used by the computer.
Only one surface of the USB plug has one row of connection terminals. So, one surface of a tongue of the current USB socket has one row of connection terminals. In use, the USB plug has to be correctly inserted so that the connection terminals of the USB plug and the USB socket may be electrically connected together.
In order to ensure the inserted USB plug to be electrically connected to the USB socket, the USB plug and socket have mistake-proof designs. That is, when the USB plug cannot be oppositely inserted, the user has to turn the USB plug and then insert the USB plug so that the electrical connection may be ensured after the insertion.
The user usually randomly inserts the USB plug into the USB socket. So, the possibility of incapable of inserting the USB plug reaches 50%. The user often has to insert the USB plug twice in an inconvenient manner.
Furthermore, the types of the plugs are gradually increased day after day. Also, the USB plugs having the same external shape may have different connection interfaces. If two plugs having the same external shape but different connection interfaces may be inserted into and electrically connected to the same socket, the usage of the socket may be diversified.